The SNARC (spatial numerical association of response codes) effect refers to an association between numbers and spatial properties of responses. The effect occurs in a multitude of stimulus notations, such that it is commonly thought to be amodal and notation-independent. In two experiments, we tested for a horizontal SNARC effect in participants from mainland China in Arabic digits, simple-form Chinese characters and Chinese hand signs to investigate whether the spatial mapping of numbers varied between notations with different visuospatial properties. We found a horizontal SNARC effect in all notations, the first time that a horizontal SNARC effect has been demonstrated in Chinese characters and Chinese hand signs. Chinese hand signs and Chinese characters were of particular interest to us, as these notations are represented non-symbolically through numerosity for low numbers (1…5 and 1…3, respectively) but symbolically for higher numbers, thus giving us a control condition within the same notation to investigate effects of numerosity on the processing of numbers. Our data indicate that numerosity is processed in parallel to number magnitude and substantially influenced the strength of the SNARC effect. We discuss both purely perceptual mechanisms for this influence, considering processing times and the different visual complexity of symbolically and non-symbolically represented numbers, and cognitive mechanisms taking into account previous studies on the role of reading and finger counting habit in numerical processing.